Photographic shutter with adjustable flash synchronizing mechanism



Oct. 13, 1953 1 K. GEBELE PHOTOGRAPHIC SHUTTER WITH ADJUSTABLE V FLASHSYNCHRONIZING MECHANISM Filed June 23, 1951 v vaiorjzeg Patented Oct.13, 1953 ABLE FLASH NISM SYNCHRONIZING MECHA- Kurt Gebele, Munich,Germany, assignor to Hans Deckel, Munich-Solln, Germany, and FriedrichWilhelmDeckcl, Post Tutzing, Germany Application June 23, 1951, SerialNo. 233,194 In Germany April 10, 1951 3 Claims. 1

The present invention relates to a photographic objective closure havingone or more contact arrangements for the flashlight circuit,'at'leastone of which can be set 'atvarious preignition times for takinginto account the respective flashlight illumination retardation.

In conventional objective closures it is customary to set thepreignition time of the contact arrangement according to the selectedillumination time with the help of a special, manuallyoperatedsetting-member. However, this manual setting which is necessary'eachtime, for example, in changing the lighting time, delays considerablythe insert readiness of the camera, because it requires of the operative"great care and a precise knowledge of the respective operatingconditions, and, specifically, both for each of the closing times andfor various lamp types. At a rapid succession of exposures, orwith aninsufficiently trained operative, incorrect lighting-due to incorrectsetting is scarcelyavoidable.

Ithas, therefore, been sought in photographic objective closures toeliminate these disadvantag'es by providing, instead of an arbitraryset- While this arrangement facilitates the manipulation of the setting,it does not allow any intermediate values for flashlights withillumination retardation.

Furthermore proposals have been made for a rigid association of the timesetting member with a control cam for the purpose of the additionalcontrol of the manually adjusted-contact setting member by said controlcam during the time-setting, so that a superposition of the preigni'tiontime setting is done automatically with the time setting. Since,however, the range of superposition merely for a single lamp type has tocorrespend with the full range of the time setting, in order to obtainan exact point of ignition setting, there follows the disadvantage atthis construction that it being applicable only for a single controlrange, that means for a single lamp type.

One object of the present invention is to avoid the reciteddisadvantages of prior arrangements and to provide an objective closurewith a contact arrangement of simple and exact operation.

Another object of the invention is to provide on the objective closure acontact arrangement, which enables control of the pro-ignition time in aplurality'o'f different ranges.

The'enumerated features of the invention will be more fully understoodfrom the following specification by reference to the accompanyingdrawings, in which:

Figure 1 shows a closure of my invention with the cover plate removedand unimportant parts omitted; Fig. 2 shows a front view of theclosure;Fig. 3 is a fragmentary sectional view showing the details of theclosure on an enlarged scale;

Fig. 4 is a fragmentary plan view of the closure of Figs. 1-3 on anenlarged scale; Fig. 5 is a detail sectional view of the settingmechanism; and Fig. 6 shows on an enlarged scale the coaction of theoperating parts of the mechanism of my invention.

Referring to the drawings in detail, reference character in designates aclosure housing in which there is rotatably mounted a trigger -l2,displaceable out of the resting position in Fig. 2 into the positionshown in dotted lines in Fig. 1 as the closure drive mechanism iscooked. A releaser I4 is provided for releasing the closure and forsetting the various lighting times, a rotatable time-setting ring l6,whose setting mark [8a collaborates with the time scale 22 provided onthe cover plate 20 1s provided. I

For exposures with the flashlight there is disposed in the closurehousing a contact arrangement for the flashlight circuit. For conductiveconnection of this contact arrangement with the rest of theeelctricalequipment there is provided a two-pole contact connector 2 1, over whichthere can be applied a suitable contact plug having coasting contactsthereon. One pole of the connector 24 is connected with the mass of themetal closure parts. The pole is connected through an insulated'lead 26in the closure housing. This lead is in turn connected with the mass ofa double-armed contact lever 28, which is rotatably mounted on aninsulated peg 30. A contact pin 32 serves as a pivot for angularlymovable countercontact member of the contact lever 23 or harmonizingorgan 3%, which is, together with others of the closure parts, connectedwith the closure housing.

The angularly movable member 34 is a lighting harmonizing arrangement.The member 34 is mounted to oscillate in the closure housing I!) and istensioned and biased by a power source of its own, for example, by aspring, which when the closure trigger i2 is actuated, is 'tensioned atthe same time. The tensioned position of the movable member orharmonizing organ 3 is represented in Fig. 1. When the releaser I4 isactuated there is first released the movable member or harmonizing organ36, so that, through the intermediary of a retarding mechanism, notshown, but suitably retarded, it moves in the direction of the arrow, indoing which, after the contact pin 32 has moved into abutment with thecontact lever 23, the lighting circuit is closed. A short timethereafter, through a further movement of the movable member orharmonizing organ 34, there is brought about the release of the actualclosure course, in such a way that the closure sectors of the irisshutter 36 are opened and again closed in the familiar manner.

The preignition time of the contact arrangement due to the illuminationretardation of the flashlamp corresponds to the distance from each otherof the contact parts 28, 32. The preignition time must always beselected according to the set lighting time. For this purpose thecontact lever 28 can be set in various positions relatively to thecontact pin 32, in that its arm 38 is swung over an isolated projection40, with the help of a guide cam 42 of a guide ring 44 mounted in theclosure housing.

The guide ring 34 is, according to Fig. 3, connected through theintermediary of a plurality of screws "55, with a setting ring 38, whichis mounted in the closure housing Iii above the time setting ring [5.Its rim extends beyond the front side of the closure, and possesses formanipulation a milling 50. The set ring 48, B and hence also the guidering 12, i i, are positioned over 'a plurality of snap springs 52, whichsit in the time setting ring 16, and engage in correspondinglydistributed rests 55 in the set ring 38, 50 (Fig. 4), coupled with thetime setting ring l6. In this way, in setting the desired lighting time,through rotation of the time setting ring IS, the set ring 42, M is alsomoved, and the contact lever 23 is automatically set at the preignitiontime of a flashlight corresponding to the set lighting time.

As already stated in the beginning, the control of the preignition timecan also, for the purpose of taking into account the illuminationretardation of different flashlights, be undertaken in a plurality ofdifferent ranges. For this purpose the guide cam t2 is given such a formthat it exhibits three different control ranges, f, m and 3. Each ofthese control ranges assures an automatic setting of the preignitiontime within a particular flashlight class. I provide a calibration orstroke mark 56 on setting ring 50 for enabling a simple setting of theparticular control range desired relatively to the setting ring 50 andthe time setting ring which collaborates with a system of marks F, M, Son the time setting ring is corresponding to one of the most Widelyrotated until the desired setting occurs. In doing so the snap springs52 fall into other rests 54.

. If now, it is desired to set a lighting time, for example, /2 second,as can be seen in the setting shown in Fig. 2, then, with the settingmovement of the time setting ring E6 .of the guide ring 44, as well asthe range m of its guide cam 42, the rings are brought into a position,and the contact lever 28, 38, 40 is swung into a position relatively tothe countercontact pin 32 which assures the necessary preignition timefor this lighting time.

According to this setting there follow in sequence the tensioning andrelease of the closure, and hence the execution of a flashlightexposure, in the manner already explained above.

If, now, the operative, for special reasons desires to employ anotherflashlight class for another exposure, then all he has to do is tochange the setting of the setting ring 48, 50, relatively to the systemof marks on the time setting ring l6, while the actual setting of thepreignition, as described, occurs automatically through the time settingring It in setting the new light time.

- Besides the described contact arrangement for flashlights withillumination retardation there is also often built into the closure asecond contact arrangement for flashlamps without illuminationretardation (X lamp class). The latter functions in such a way that,having inactivated the first contact arrangement, the second con.- tactarrangement does not close the flashlight circuit until the closuresectors are present in the open position. For this purpose this contactarrangement is usually closed by a running down closure mechanism. Sucha contact arrangement is described hereinafter.

In the closure housing Hi there is mounted a double armed lever 58. Itis subject to the action of a spring 60, which strives to swing an arm62 of the lever 58 clockwise, and press it on the lower edge 64 of thesetting ring 48. The other arm 66 of the lever 58 lies in theneighborhood of the annular wall of the closure. This arm 66 isinsulated, and collaborates with an exposed contact end 68 of the lead26 in such a way that it holds it against an insulated piece 70 of theannular Wall of the closure. As soon, however, as the lever 58 is ableto move farther clockwise out of the position shown in Fig. 1, thecontact end 68 comes into the range of a projection 12 of the closuretrigger l2, which is, together with the rest of the closure parts,connected with the mass pole. Thus, when the tension ring l2 runs down,the circuit is closed. The above-mene tioned farther swinging of thelever 58 is enabled by a recess 14 in the lower edge 64 of the settingring 48, into which the end 62 of the lever is able to enter at aparticular position of the setting ring 48, 50. I

In the event that under employment of the X lamp class, the contactarrangement 28, 32 does not close the circuit prematurely, there isprovided a suitable safety provision, The latter consists in that, insetting the stroke mark 56 at a mark X of the time setting ring [6, thecontrol range a of the guide cam 42 collaborates with and swings thecontact lever 28, 38, 40 in such a way that it is unable to reach thecontact pin 32 untilafter the circuit has been closed by the othercontact arrangement 68, 12 7 Of course, the control system could also bearranged in such a way as to enable the employment of flashlights bothwith and without illumination retardation with a single contactarrangement. Finally, it should also be noted that the division of thecontrol range could occur not only according to the lamp cIasses butalso according to other viewpoints, for example, according to the peaktime of the flashlights.

While I have described my invention in cer- 5 tain preferredembodiments, I realize that modifications may be made and I desire thatit be understood that no limitations are intended other than may beimposed by the appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is as follows:

1. In a photographic objective closure, in combination, a photographicshutter, time setting means on said shutter permitting the settingthereof at difierent exposure times, a flashlight-contact arrangementand a flashlight-synchronizer mechanism built in said shutter, saidcontact arrangement being closed by a part of saidflashlight-synchronizer mechanism in set pre-ignition time with respectto the opening of said shutter for taking into account respectiveflashlight delays of different flashlamps, a cam member adjustablymounted in said shutter and cooperating with said contact arrangementfor setting the latter in various pre-ignition times, said cam memberhaving a plurality of control ranges thereon deviating from each otherfor the purpose of taking into account different flashlight delays ofdifierent flashlamps, and disengageable coupling means arranged betweensaid time setting means and said cam member for positioning a selectedone of said control ranges on said cam member in selective relationshipto 6 said contact arrangement and to said time setting means and formoving said member in proportion to the movement of said time settingmeans, whereby the setting of said contact arrangement in variouspre-ignition times occurs at each flashlamp in the selected relationshipautomatically with the time setting of said shutter.

2. A photographic objective closure as set forth in claim 1, in whichsaid coupling means is provided with snap springs arranged in said timesetting ring and engageable in distributed rests in said cam member.

3. A photographic objective closure as set forth in claim 1, whichincludes a second contact arrangement for flashlamps without flashlightdelay, said cam member being provided with an additional control rangefor setting said first contact arrangement proportionally to the settingof said second contact arrangement.

KURT GEBELE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,514,302 Aiken July 4, 1950 2,563,782 Fuerst Aug. 7, 19512,596,871 Fuerst May 13, 1952

